NERVOUS SYSTEM Flashcards
serve as communication lines among sensory organs, the brain and spinal cord, and glands or muscles
PERIPHERAL NERVOUS SYSTEM
command center, Interprets incoming sensory information
CENTRAL NERVOUS SYSTEM
carry impulses to and from the spinal cord
SPINAL NERVES
carry impulses to and from the brain
CRANIAL NERVES
transmits electrical signals called, action potential, from sensory receptors in the body to the CNS.
SENSORY DIVISION / AFFERENT DIVISION
carry information from the skin, skeletal muscles, and joints
SOMATIC SENSORY (AFFERENT) FIBERS
carry information from visceral organs
VISCERAL SENSORY (AFFERENT) FIBERS
nerve fibers that carry impulses away from the central nervous system organs to effector organs
MOTOR DIVISION / EFFERENT DIVISION
consciously (voluntarily) controls skeletal muscles
SOMATIC NERVOUS SYSTEM = VOLUNTARY
automatically controls smooth and cardiac muscles and glands
AUTONOMIC NERVOUS SYSTEM = INVOLUNTARY
▪ the “fight-or-flight” division
▪ most active during physical activity
SYMPATHETIC DIVISION
▪ The “rest-and-digest” division
▪ Regulates resting functions, such as digesting food or emptying the urinary bladder
PARASYMPATHETIC DIVISION
receive stimuli, conduct action potentials, transmit signals to other neurons or effector organs
NEURONS
nucleus and metabolic center of the cell
CELL BODY
fibers that extend from the cell body
PROCESSES
support and protect neurons and perform other functions / Helps form a protective permeability barrier between the blood and the brain and spinal cord
GLIAL CELLS
the source of information for protein synthesis
NEURON CELL BODY
Branching organizations / conduct impulses toward the cell body
DENDRITE
conduct impulses away from the cell body
AXONS
functional junction between nerves where a nerve impulse is transmitted
SYNAPSE
Have many dendrites and a single axon / most of the neurons within the CNS and motor
MULTIPOLAR NEURONS
Sensory neurons found in PNS ganglia / Conduct impulses both toward and away from the cell body
UNIPOLAR NEURONS
Have two processes: one dendrite and one axon / The dendrite is often specialized to receive the stimulus, and the axon conducts action potentials to the CNS.
BIPOLAR NEURONS
Have a single process extending from the cell body, which divides into two branches
PSEUDO-UNIPOLAR NEURONS
Protect neurons from harmful substances in blood / Control the chemical environment of the brain
ASTROCYTES
Spiderlike phagocytes / CNS-specific immune cells / Become mobile and phagocytic in response to inflammation
MICROGLIA
▪ Line the ventricles (cavities) of the brain and the central canal of the spinal cord
EPENDYMAL CELLS
Wrap around nerve fibers in the central nervous system
OLIGODENDROCYTES
major positive ion inside the cell
K+
major positive ion outside the cell
NA+
The inward rush of sodium ions changes the polarity at that site
DEPOLARIZATION
Membrane permeability changes again—becoming impermeable to sodium ions and permeable to potassium ions
REPOLARIZATION
Rapid, predictable, and involuntary responses to stimuli
REFLEX
Reflexes occur over neural pathways
REFLEX ARCS
Reflexes that stimulate the skeletal muscles
SOMATIC REFLEXES
Regulate the activity of smooth muscles, the heart, and glands
AUTONOMIC REFLEX
reacts to a stimulus
SENSORY RECEPTOR
carries message to the integration center
SENSORY NEURON
processes information and directs motor output
INTEGRATED CENTER (CNS)
carries message to an effector
MOTOR NEURON
is the muscle or gland to be stimulated
EFFECTOR ORGAN
a sensation characterized by a group of unpleasant and complex perceptual and emotional experiences that trigger autonomic, psychological, and somatic motor responses.
PAIN
pain-relieving medications
ANALGESICS
a painful sensation in a region of the body that is not the source of the pain stimulus.
REFERRED PAIN
occurs in people who have had appendages amputated or a structure, such as a tooth, removed.
PHANTOM PAIN
Characterized by muscular rigidity; loss of facial expression; tremor; a slow, shuffling gait; and general lack of movement.
PARKINSON’S DISEASE
caused by muscle tension. They consist of a dull, steady pain in the forehead, temples, and neck or throughout the head.
TENSION HEADACHE
usually occur on only one side of the head and appear to involve a combination of neurological dysfunction and abnormal dilation and constriction of blood vessels.
MIGRAINE HEADACHE
